Jack



W. C. KIRK, SR.

l l JACK. APPLICATION FILED. MAR.2I. 1921.

1,418,654, A mmm... 6,1922.

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siren rastrear ricerca WILLIAM C. KIR-K, SR., 0F CHATTAN'OOGA, TENNESSEE.

JACK.

Specification of Letters .Patent Patented I une 6, 1922.

Application led March 21, 1921. SerialY No. 454,048.

Chattanooga, in the county of Hamilton and State of Tennessee, have invented certain new and useful Improvements in Jacks, of which the :following is a specification.

This invention relates to improvements in jacks, and the particular yadaptation which has been selected for the purposes of illustration is a hand jack such as is in common Yuse for elevating one end of an automobile in changing tires.

In jacks of this type it has been common to employ mechanism requiring the use of a socket and handle, which is designed to be lifted and depressed under the control of a ratchet andpawl to raise thev lifting element or rack bar, and to change the position of certain of the parts and repeat the operation to accomplish the descent of the lifting element of rack bar. By this invention it is only necessary to use the ordinary tire tool to produce a rotary motion which accomplishes the raising of the lifting element, while a reverse rotary movement will accomplish the descent.

The invention has for its object the production of a jack, which will be easy of operation and eflicient in use. Another object is the production of a jack in which the raising force is applied through the medium of a friction clutch, 'the frictional pressure between the clutch members being proportional to the weight of the load. It has for a further object the production of jack incorporatino' such a frictional clutch, which avoids any thrust action between the parts.

Other objects and advantages'of the in* vention will hereinafter appear in the following descriptionand the novel features thereof will be particularly pointed out in the appended claims.

In the drawings, in which like parts are represented by like reference characters,

Figure 1 is a side elevation of the jack with cover plate removed, Figure 2 is a section upon the line 2-,-2 of Figure l, Figures 3 and t are enlarged detailed views of the swivel head and pivoted foot of the jack, respectively, vthese views being sections taken upon the line 3 -4 of Figure 1, and

Figure 5 is a like View taken at a righty angle to Figure 4f.

The numeral 10 represents the casing of the jack, which at i larged into a gear casing 11. In this gear casing there is journaled the power shaft 12 and the eouutershaft 13. Tothe shaft 13 is keyed Aor otherwise secured a rack pinion and the large transmission pinion The rack bar or lifting element is designated by the numeral 16 and travels in the vcasing l() under the influence of the rack pinion 141.

. Upon the shaft 12 at one end there is keyed the small transmission pinion 17 opposite end abutting shoulder 22 there is splined the disk 18 of the friction clutch. Slidably mounted and freely rotatable upon said shaft 12 is a cup element 1S) of the the upper portioniis enand at the friction clutch, cooperating with the disk of said clutch, and between these two clutch elements there is placed a friction washer 20 of any suitable material, leather having been selected for the purpose of illustration.

The shaft 12 is provided'with a screw `v:

threaded end 23 projecting beyond `the gear casing, upon which is mounted the force nut 24, by means of which .the clutch members 18 and 19 are brought int-o frictional engagement, or released from said kengagement. In order to prevent the r'force nut from being unscrewed from the shaft.: end 23, there is provided a locking disk 25 atthe extremity ofk said shaft, whichis heldin place by the machine screw 26.

It will be noted that the cupped clutch r member 19 is provided upon its periphery with ratchet teeth 27, with which engage a pair of staggered pawls 28 and 29 supported by the gear case by means of the pin 30 and held in contact with the ratchet periphery of the clutch member by means of the spring 31.

The gear casing 11 is openvat bot-h sides for the purpose of assembling the several i: I

parts therein,y and the cover plates 32 and 33 are provided to protect the parts vfrom the dust, screws 34: being-shown as the means for securing said plates to the casing. It is obvious that the gear case has beenso lformed .4

as to conveniently. accommodate Athe several parts and protect them in use.. f

At its upper end therack bar 16 is pro-y vided witha swivel head 35 which is 'curved throughout its length tolmore efficiently en-y .1.

gage the portion of the automobile axle or axle casing. This head is secured to the rack bar by means of the rivet extension to the said bar. `The lower end of the casing 10 is pivotally mounted upon the foot member, which is generally designated by 'the numeral 36 and which comprises the base 37, the lugs 38 and B9 provided with suitable openings Vto receive the bolt el-O passing through the sides of the casing or column and through the lugs, and held in such position b y means of the nuts 4t2 and 43. Suitable locking washers 4a and 45 are provided if found necessary. rlhis `construction of foot member is desirable in order to obtain aneven and secure footing for the jack upon uneven ground. At its lower end the rack is provided with a notch 4l-1 which straddles the bolt 40. The teeth of the rack are not extended to the bottom thereon, and the untoothed portion with the teeth on the `pinion 11i constitutes a means to prevent accidental withdrawal. of the rack from the casing. The lower end of the casing or column rests upon the base 37 and is curved to permit of pivoting thereof within certain limits without destroying its contact with the base, itbeing understood that the relative size of bolt et() and its receiving apertures will permit this result, or provision may be made for a curved seat L16, as shown on `the drawing.

lt will be noted that the pivoted foot member, the swivel head and the rotative application of power combine to produce a jack which is capable of use in any position made necessary by unevenness of ground or other causes.

The operation of the device may be readily understood from the foregoing description. The jack is placed under the axle or axle casing of an automobile and the ordinary tire tool is placed upon the nut Q-l, which is then turned in a clockwise direction, bringing the nut into contact with the cupped clutch member 19 and upon continued movement of the nut rthe cupped clutch member is brought into firm frictional contact with the disk clutch member 18 keyed to the shaft 19. and abutting shoulder 22. This avoids inV the tightening of the clutch any thrust action between the clutch members and parts of the casing and determines the amount of frictional pressure between the clutch members 18 and 19. llVhen these members are in sufficiently firm contact, continued turning movement of the nut will cause the shaft 12 to turn with the clutch members, when motion will be trans mitted through the small gear 17 to the large gear 15 and rack pinion 11.4-, causing the rack bar 16 to be elevated. Since the frictional pressure between the clutch members is sutlicient to cause the turning of the shaft `12, it will be appreciated that the turning `motion of the tire tool may lbe arrested at any point, as the frietional contact will be sullicient to hold the load, it `being understood that the cupped clutch member `will be held by the pawls 52S and 29 cooperating with the toothed periphery.

To release the jack, it is only necessary to apply the tire tool to the nut 24, and turn the same slightly in a countercloclwise direction, when the frictional contact between the clutch members 18 and 19 will be relieved just enough to cause the weight of the load to transmit a reverse motion through the several gears to the shatt 1:2, which will tend to draw the nut back to reestablish the frictional contact between the clutch members. the descent of the load will be easily accomplished and will be ever under the control of the user of the jack, and that the speed of descent can be either fast or slow as the operator wills.

It will be observed that by this construetion there is produced an eilicient jack, which can be used for both raising and lowering the load without resetting ot parts` that there no thrust between the parts, and that it reipiires for its operation no special handle, other than the ordinary tire tool` which is carried by all automobile-:

llv'hilel have shown and described one form of my invention, it will be understood that this form is for the purpose of illustration only, and that the invention is susceptible of many embodiments without departing from the spirit thereof as defined by the appended claims.

What is claimed is:

1. In a jack comprising a supporting casing, a lifting element mounted for vertical movement within said casing, a `power shaft and means for transmitting motion from said power shaft to said lifting element, a friction clutch upon Said power shaft comprising fixed and movable mem-- bers, and means for moving said movable member into frict-ional engagement with said ixed member, in application of power to the jack. A

2. In a jack comprising a supporting `casing, a lifting element mounted for vertical. movement within said easing, a power shaft and means for transmitting motion from said power shaft to said lifting element, a

friction clutch upon said power shaft comprising fixed and movable members, and means for controlling the frictional engagement of said clutch members and for rotating said power shaft.

3. In a jack comprising a supporting casing, a lifting element, a power shaft and means for transmitting motion from said power shaft to said lifting element, a friction clutch comprising a member fixed upon said power sha-fha movable member rotatably mounted upon said power shaft,

lt will thus be seen that means for forcing said members into frictional Contact and for rotating said power shaft thereafter, and means for holding said movable member against retrograde rotative movement, whereby the lifting element will be held in an elevated position until the frictional contact of the clutch members is released.

4. In a jack comprising a supporting casing, a lifting element, a power shaft and means for transmitting motion from said power shaft to said lifting element, a clutch member rotating with said power shaft, a second clutch member rotatably mounted upon said power shaft, means for forcing said clutch members into frictional contact, whereby upon rotation of said movable member the liftin element will be elevated,

n and means for ho ding Said movable member against retrograde rotative movement, whereby the lifting element will be held in its elevated position until the release of the clutch members is accomplished.

5. In a jack comprising a supporting casing, a lifting element, a power shaft and means for transmitting motion from said power shaft to said lifting element, said power shaft having a screw threaded end, a clutch member fixed upon said power shaft, and a second clutch member rotatably mounted upon said shaft, and means mounted upon said screw threaded end for causing the clutch members to be engaged and the power shaft to be rotated.

6. In a jack comprising a supporting casing, a lifting element, a power shaft and means for transmitting motion from said power shaft to said lifting element, said power shaft having a screw threaded end,.

fixed and movable clutch members upon said power shaft, an interior-ly threaded oper ator cooperating with said screw threaded end, whereby a rotation of said operator in one direction will cause the clutch members to be engaged and the shaft rotated to elevate the lifting element while a rotation of said operator in the opposite direction will relieve the frictional engagement of the clutch members and permit a controlled descent of the lifting element.

7. In a jack comprising a supporting casing, a lifting element, a power shaft and means for transmitting motion from said power shaft to said lifting element, said power shaft having a screw threaded end, fixed and movable clutch members mounted upon said powerpshaft, a nut upon said screw threaded end cooperating therewith to cause engagement of said clutch members, means for holding the movable clutch member against retrograde rotative movement, and means for maintaining the nut upon said power shaft.

8. In a lifting jack, an operating mechanism comprising a power shaft having a 'screw threaded end, a clutch member fixed Vupon said power shaft, a movable clutch member rotatably mounted upon said shaft, and an operator having a threaded bore for cooperation with said. screw threaded end, whereby a rotation of said operator relative to said shaft will cause theclutch members to engage and a further rotation of said operator will cause the power shaft to rotate.

In testimony whereof I affix my signature.

WILLIAM o. KIRK, sk. 

